Integrated circuit package system using etched leadframe
View Patent ↗An integrated circuit package system includes a conductive substrate. A heat sink and a plurality of leads are etched in the substrate to define a conductive film connecting the heat sink and the plurality of leads to maintain their spatial relationship. A die is attached to the heat sink and wire bonded to the plurality of leads. An encapsulant is formed over the die, the heat sink, and the plurality of leads. The conductive film is etched away to expose the encapsulant and the bottom surfaces of the heat sink and the plurality of leads. Wave soldering is used to form solder on at least the plurality of leads. Multiple heat sinks and hanging leads are provided.
1. A method of manufacture of an integrated circuit package system comprising:
providing a conductive substrate;
forming a heat sink and a plurality of leads in the substrate to define a conductive film connecting the heat sink and the plurality of leads to maintain their spatial relationship;
attaching a die to the heat sink with a thermally conductive adhesive on a non-active side of the die;
wire bonding the die to the plurality of leads;
forming an encapsulant over the die, the heat sink, and the plurality of leads;
etching the conductive film to expose the encapsulant and the bottom surfaces of the heat sink and the plurality of leads, and
dicing to expose a second surface of some of the plurality of leads along an outermost boundary and a corner of the integrated circuit package system.
2. The method as claimed in claim 1 wherein forming a heat sink and a plurality of leads in the substrate to define a conductive film selectively etches the substrate a predetermined depth.
3. The method as claimed in claim 1 wherein forming a heat sink and a plurality of leads in the substrate to define a conductive film uses a selective depth chemical etch.
4. The method as claimed in claim 1 wherein etching the conductive film to expose the encapsulant and the bottom surfaces of the heat sink and the plurality of leads selectively etches the conductive film a predetermined depth.
5. The method as claimed in claim 1 wherein forming a heat sink and a plurality of leads in the substrate to define a conductive film defines a conductive film having a thickness of about 3 mm.
6. The method as claimed in claim 1 further comprising:
wave soldering solder the plurality of leads.
7. The method as claimed in claim 1 wherein forming a heat sink and a plurality of leads in the substrate to define a conductive film forms a plurality of hanging leads.
8. A method of manufacture of an integrated circuit package system comprising:
providing a conductive substrate;
forming a first heat sink, a second heat sink, and a first plurality of leads between the first heat sink and the second heat sink, and a second plurality of leads in the substrate to define a conductive film connecting the heat sink, the first plurality of leads, and the second plurality of leads to maintain their spatial relationship;
attaching a die to at least one of the first heat sink and the second heat sink with a thermally conductive adhesive on a non-active side of the die;
wire bonding the die to the first plurality of leads;
forming an encapsulant over the die, the first heat sink, the second heat sink, the first plurality of leads, and the second plurality of leads;
etching the conductive film to expose the encapsulant and the bottom surfaces of the first heat sink, the second heat sink, and the first plurality of leads, and the second plurality of leads; and
dicing to expose a second surface of the second plurality of leads along an outermost boundary and a corner of the integrated circuit package system.
9. The method as claimed in claim 8 wherein forming a first heat sink, a second heat sink, and a first plurality of leads, and the second plurality of leads in the substrate to define a conductive film selectively etches the substrate a predetermined depth.
10. The method as claimed in claim 8 wherein forming a first heat sink, a second heat sink, and a first plurality of leads, and the second plurality of leads in the substrate to define a conductive film in the substrate uses a selective depth chemical etch.
11. The system as claimed in claim 8 wherein etching the conductive film to expose the encapsulant and the bottom surfaces of the first heat sink, the second heat sink, the first plurality of leads, and the second plurality of leads selectively etches the conductive film a predetermined depth.
12. The method as claimed in claim 8 wherein forming a first heat sink, a second heat sink, a first plurality of leads, and a second plurality of leads in the substrate to define a conductive film defines a conductive film having a thickness of about 3 mm.
13. The method as claimed in claim 8 further comprising:
wave soldering solder on at least the first plurality of leads.
14. The method as claimed in claim 8 further comprising:
forming a second plurality of leads around at least a portion of the periphery of the conductive substrate; and
wire bonding the die to the second plurality of leads.
15. The method as claimed in claim 8 further comprising:
attaching a second die to the second heat sink;
forming the second plurality of leads around at least a portion of the periphery of the conductive substrate; and
wire bonding the second die to at least some of the second plurality of leads.
16. An integrated circuit package system comprising:
a first heat sink;
a second heat sink;
a first plurality of leads between the first heat sink and the second heat sink;
a second plurality of leads including a second surface exposed along an outermost boundary and a corner of the integrated circuit package system;
a die attached to the first heat sink with a thermally conductive adhesive on a non-active side of the die;
a first plurality of wires bonding the die to at least some of the first plurality of leads; and
an encapsulant over the die, the first heat sink, the second heat sink, the first plurality of leads, and the second plurality of leads with the lower surfaces of the first heat sink, the second heat sink, the first plurality of leads, and the second plurality of leads exposed.
17. The system as claimed in claim 16 further comprising:
a second plurality of leads around at least a portion of the periphery of at least the first heat sink; and
a second plurality of wires bonding a second die to at least some of the second plurality of leads.
18. The system as claimed in claim 16 , further comprising:
a second die attached to the second heat sink; and
a further plurality of wires bonding the second die to at least some of the first plurality of leads.
19. The system as claimed in claim 16 further comprising:
solder on at least the first plurality of leads.
20. The system as claimed in claim 16 further comprising:
a second plurality of leads around at least a portion of the periphery of at least the second heat sink;
a second die attached to the second heat sink;
a third plurality of wires bonding the second die to at least some of the first plurality of leads; and
a fourth plurality of wires bonding the second die to at least some of the second plurality of leads.